The objectives of this proposal are to understand the principles involved in the metabolic regulation of normal and abnormal erythrocytes. Particular emphasis will be placed on the investigation of those enzymes responsible for the synthesis, degradation, and utilization of glycerate-2,3-P2. The enzymes of special interest are bisphosphoglycerate synthase, phosphoglycerate mutase, and phosphoglycerate kinase. This study will include an evaluation of certain regulatory substances and intracellular environmental conditions which might ameliorate sickle cell anemia, other cardiovascular disorders, and blood storage problems.